1. Field of the Invention
The present invention concerns the fixation of a pump in a beverage preparation machine, in particular the fixation of a reciprocating piston pump.
For the purpose of the present description, a “beverage” is meant to include any liquid food, such as tea, coffee, hot or cold chocolate, milk, soup, baby food, etc. . .
2. Background Art
Beverage preparation machines have been known for a number of years. For example, U.S. Pat. No. 5,943,472 discloses a water circulation system between a water reservoir and a hot water or vapour distribution chamber of an espresso machine. The circulation system includes a valve, metallic heating tube and pump that are connected together and to the reservoir via different silicone hoses, which are joined using clamping collars. Suitable pumps for beverage machines are for instance disclosed in U.S. Pat. Nos. 2,715,868, 5,392,694, 5,992,298, 6,554,588, WO 2006/032599 and WO 2009/150030.
For instance, U.S. Pat. No. 2,715,868 discloses a beverage preparation machine for extracting a beverage ingredient within an extraction chamber supplied in a cartridge by water guided into the extraction chamber and forced through the cartridge. The pump is of the rotary type and has blades operating in a pump chamber to transfer liquid under pressure to the extraction chamber.
U.S. Pat. No. 5,392,694 discloses an espresso machine with a piston pump mounted in the machine's housing. The pump has a reciprocating piston that is actuated by an eccentric drive having a connecting rod that is engaged with the piston.
U.S. Pat. No. 5,992,298 discloses a beverage preparation machine with a vibrating pump suspended in mobile or overhung manner, the vibrations being transferred to an in-line heater to vibrate the heater with the view of reducing liming in the heater.
U.S. Pat. No. 6,554,588 discloses a composite piston for vibration pumps suitable for use in espresso machines.
In general, during operation of the pump of such a device, vibrations occur due to an oscillating or rotational movement of a driven part, e.g. a piston or a number of blades, housed within a pump chamber of the pump. These vibrations may then be transferred to the housing of the device and thus negatively affect the quality or operational feel of the beverage preparation device. Moreover, the vibrations may negatively affect other components housed within the housing of the device.
To address this problem, it has been proposed in WO 2006/032599 to suspend the pump in the beverage preparation machine with spaced apart suspenders.
In WO 2009/150030, it has been proposed to support the pump with an elastic leaf support, e.g. a bellow-shaped elastic support member.